In a wireless communication system, a base station is a device for providing services to terminals and communicates with terminals over uplink/downlink, wherein downlink refers to the direction from the base station to a terminal, and uplink refers to the direction from a terminal to the base station. As for data transmission, a plurality of terminals may transmit data to a base station over uplink simultaneously and receive data from the base station over downlink simultaneously. In a wireless communication system that adopts a base station to achieve radio resource scheduling and control, the scheduling and allocation of system radio resources is performed by a base station, for example, the base station provides downlink resource allocation information when the base station performs downlink transmission and uplink resource allocation information when a terminal performs uplink transmission.
In a wireless communication system that is put into commercial use, a base station generally takes a radio frame as a scheduling period when scheduling air interface radio resources, and partitions radio resources into a plurality of radio resource units (for example, a time slot or a codeword) for scheduling. During a scheduling period, the base station provides data or multimedia services to terminals within its coverage by scheduling the radio resources units. For example, in a 2G wireless communication system represented by GSM (Global System For Mobile Communication), a base station partitions radio resources at each frequency into TDMA (Time Division Multiple Address) radio frames with a period of 4.615 ms, each radio frame comprising 8 time slots, each time slot may transfer a session of one full rate or two half rates and also achieve a low-speed data service; in a 2.5G wireless communication system represented by GRPS (General Packet Radio Service), a data service rate is increased to above 100 kps by introducing fixed time slot-based packet switch; and in a 3G wireless communication system represented by TD-SCDMA (Time-Division Synchronization Code Division Multiple Address), a base station likewise partitions air interface radio resources into radio frames with a period of 10 ms, each 10 ms comprising 14 normal time slots and 6 special time slots, wherein the normal time slots are used to transmit specific services and signaling, in each normal time slot, the base station distinguishes users through different codewords.
Future wireless communication systems represented by LTE (Long Term Evolution), UMB (Ultra Mobile Broadband) and IEEE 802.16m, due to the use of OFDM (Orthogonal Frequency Division Multiplexing) and OFDMA (Orthogonal Frequency Division Multiple Address) technologies, provide technical support for the supply of high-speed data and fluent multimedia services, meanwhile impose new restraints on radio resource management.
Firstly, increasing communication services cause increasing system bandwidth occupied by a future wireless communication system, while continuous large bandwidth becomes less and less. In order to fully utilize scattered frequency resources, the future wireless communication system is required to support a multi-carrier bear, thus making resource mapping of future radio resources more complex. Secondly, in order to support terminals of different types or different capabilities, service types required to be supported in the future become more and more, and the demands on QoS (Quality of Service) of these different service types are different, so are the demands on radio resource units, especially VoIP (Voice over IP) data packets and small control class messages; in addition, interference has become a main bottleneck for the development of wireless communication systems, so a new resource mapping method is needed in order to support interference inhibition measures such as FFR (Fractional Frequency Reuse) and services such as EMBS; finally, channel environment of wireless communication often changes, and resource units also have various types, such as localized resource units and distributed resource units; such change also requires that resource mapping have the capability of supporting these new features.
Therefore, a traditional radio resource unit (such as a time slot or a codeword) and its corresponding sub-channelization and resource mapping process cannot satisfy the demands of future wireless communication systems. In order to guarantee the spectrum efficiency of future wireless communication systems, it is necessary to design a new sub-channelization and resource mapping method for radio resources.